A central rail-guided vehicle is a vehicle usually made up of a plurality of wagons and circulating on rubber tires, which bear the weight of the vehicle and provide it with the tractive and braking efforts required in traffic. The surface on which these vehicles circulate is generally urban streets but on exclusive roadways, similar to tramways.
A specially-shaped central rail is arranged embedded in the surface for guiding said vehicles. Two railway-type wheels assembled in one and the same truck or bogie in the vehicle such that their axles form an angle of about 90° are supported on said rail. The arrangement of said wheels and the special shape of the central rail are what guide the vehicle, such that said vehicle must follow the path marked by said central rail. For the guiding to be effective four trucks or bogies are arranged for each wagon of the vehicle, said trucks or bogies having a pivoting arrangement with respect to the body of the wagon similar to the wagons of a railway or tramway.
Like tramway or railway vehicles, these central guide systems have railway layouts such as turnouts and diamond crossings. Diamond crossings are the railway layout where two tracks cross or intersect one another, in the case of central rail-guided vehicles they are the railway layout where two guide rails cross or intersect one another. Said diamond crossings are generally embedded in the surface.
Given that these systems are conceived for being installed in the urban layout, the radii of the curves in which the vehicles must be inscribed are generally smaller than the radii of the curves of common railway vehicles, as occurs in the case of tramways. This means that like in the case of tramways, the angles of the diamond crossings for central rail-guided vehicles are greater than those corresponding to railway operations.
The fact that the central guide rail is simultaneously active on both sides of the head provides diamond crossings intended for central rail-guided vehicles with a different configuration with respect to diamond crossings of railway or even tramway. Due to this characteristic of the central guide rail, in diamond crossings intended for vehicles of this type there can be no voids, i.e., interruptions in the guide rail, given that guiding must be continuous.
Diamond crossings with a pivoting central panel have been used today for the purpose of meeting the preceding requirement. In this type of railway layout, the central panel consists of a guide rail on a platform that can rotate the angle required for selectively connecting either two branches corresponding to a first route or two branches corresponding to a second route. Both routes cross each another at the central point of the diamond crossing.
The problem with this railway layout results from the fact that the rotating shaft of the central panel is located precisely below said central panel, such that accessibility thereto is complex when performing inspection or maintenance tasks.
Additionally, in central rail-guided systems it is common, for safety and maintenance reasons, for the mechanical system made up of the railway layout, in this case the diamond crossing, the control system, i.e., the drive motor, and the locking system to be required to not invade the area of the surface intended for the rolling of rubber tires. This means that both the control system and the locking system must be as compact as possible, which on the other hand complicates maintenance and inspection.